header {
  display: block;
  background-color: black;
  width: 100%;
  height: 50px;
  color: white;
}
#headerButtons {
  list-style-type: none;
  margin: 0;
  padding: 0;
}
.navButton {
  float: right;
}

html, body, #app, #app>div {
  height: 100%
}